Duracell work but not eneloop

Wurkkos

Tulip bush

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Hi all, I use eneloop xx in my fenix tk41 and they work well. Now my usual cheap blood pressure machine batteries ran out so in I pop four freshly charged hardly used eneloop xx only to find they were not up to the job.....or was it my b pressure machine that was faulty. Well I got four of the cheapest duracell from pound land and they work the machine so well. Is this because they are 1.5v and the eneloops are 1.2v? I don't know much about batteries, but I must admit I was a bit disappointed. Comments appreciated.
 

WalkIntoTheLight

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The BP machine must require higher voltage to work than what NiMH cells offer. IMO, that's a poor design because alkalines still have plenty of capacity after dropping down to 1.2v, so it's wasting batteries.
 

mcnair55

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I find this totally strange.DAB radios are very high drain and far more testing than most flash lights and any eneloop type will power one up.I have just put freshly charged standard eneloops in my bp monitor and all is working ok.
 

WalkIntoTheLight

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I'm not sure how much current a BP monitor uses, but probably not much. Alkalines would still provide a high voltage under a light load. Freshly charged Eneloops might provide 1.35v, but fresh alkalines would be over 1.5v. It might be that his machine cuts out around 1.35v. Bad design, because it means that you can't use NiMH cells or even alkaline cells that still have half their capacity left at which point they'd be around 1.25v.
 

TEEJ

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Some electronics don't work well with 1.2 v cells (Nimh), its just the way they are wired.

Some track pads, mice, etc, for example, don't always work well with Nimh.
 

mcnair55

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Some electronics don't work well with 1.2 v cells (Nimh), its just the way they are wired.

Some track pads, mice, etc, for example, don't always work well with Nimh.

I have just one brand of torch that will not work on eneloop at all but will with other eneloop type,always found that strange but just live with it now.
 

tatasal

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Hi all, I use eneloop xx in my fenix tk41 and they work well. Now my usual cheap blood pressure machine batteries ran out so in I pop four freshly charged hardly used eneloop xx only to find they were not up to the job.....

Does the 'low batt' symbol light up with the Eneloops? Are your getting exaggerated readings? I use a set of 4 Duraloops or 4 Eneloop AAA's in mine and never had a problem. (My BP monitor is an Omron, btw)
 

Tulip bush

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Thank-you all for your comments. The blood pressure machine is a Lloyds pharmacy medical BPII...model number KD002.
I don't have an adaptor for it, but it can use one...6V DC. I does say power 4 x 1.5V. I do totally agree that it's a let down for the machine not to run on these. From hitting the start button you can feel the difference, the duracell really powers the machine whereas the eneloop just doesn't set off with such gusto and the machine stops after around 10 secs. The batteries have hardly been used, so I know it's not them due to having 8 to pick from. What a shame. Cheers
Tulip bush
 

WalkIntoTheLight

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The only thing I have that won't work well on NiMH cells is my first 2xAA LED Maglite. With NiMH cells it flickers a lot, so gets very annoying to use. On alkalines, it works fine. Another 2xAA LED Maglite I bought a couple of years later works fine on both NiMH and alkaline, so perhaps Maglite improved the design or I just had a marginal unit.

Maglite does say only to use alkalines. I wonder if this is because they know their designs don't work well with lower voltage?
 

mcnair55

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Thank-you all for your comments. The blood pressure machine is a Lloyds pharmacy medical BPII...model number KD002.
I don't have an adaptor for it, but it can use one...6V DC. I does say power 4 x 1.5V. I do totally agree that it's a let down for the machine not to run on these. From hitting the start button you can feel the difference, the duracell really powers the machine whereas the eneloop just doesn't set off with such gusto and the machine stops after around 10 secs. The batteries have hardly been used, so I know it's not them due to having 8 to pick from. What a shame. Cheers
Tulip bush

Crikey that is the same machine i have and mine works fine.
 

WalkIntoTheLight

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I think if I bought a blood pressure machine today, and it did not work with NiMH cells, that would be aggravating enough that I'd need to take blood pressure medicine every time I used the machine!
 
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